PHP is a server-side scripting language, which means that it is executed on the server rather than in the client’s web browser. When a client makes a request for a PHP file through their web browser, the request is sent to the server where the PHP code is executed.

The PHP code is then parsed and executed by the server, and the resulting output is sent back to the client’s web browser in the form of an HTML page. This means that the client’s web browser does not need to understand or execute PHP code, it only needs to be able to display the resulting HTML page.

In order for this process to work, the web server must have the necessary software (such as the PHP interpreter) installed and configured to handle requests for PHP files. The client’s web browser also needs to be compatible with the HTML code that is generated by the PHP code.

Overall, PHP works by allowing web developers to create dynamic, interactive websites and web applications by writing server-side code that is executed on the server and generates HTML output for the client’s web browser to display.